1. Technical Field
The present invention relates to a wiper washer apparatus that wipes a windshield of a vehicle such as an automobile by spraying a washer liquid onto the windshield from a nozzle provided on a wiper arm, and more particularly relates to the wiper washer apparatus that can quickly recover visibility in an imaging area of an imaging device after spraying the washer liquid.
2. Related Art
A windshield of a vehicle such as an automobile is provided with a wiper washer apparatus including a washer device that sprays a washer liquid (a washing liquid) and a washer device that wipes the washer liquid, rain, and the like.
The wiper device has a wiper arm provided with a blade made of a rubber material. The wiper arm pivots on the windshield so as to reciprocate within a predetermined wiping area on the windshield, thereby wiping water or the like on the windshield.
Generally, the washer device has a nozzle fixed on a front hood or a cowl top of a vehicle and the nozzle sprays washer liquid onto the windshield. Recently, it has been proposed that the washer device have a wiper arm provided with a nozzle. Such a wiper arm is called as a wet arm.
For example, Japanese Unexamined Patent Application Publication (JP-A) No. 2008-6971 discloses a wiper washer apparatus in which a wiper arm is provided with a nozzle for spraying a washer liquid. The apparatus is provided with a spray unit that sprays the washing liquid (the washer liquid) onto the wiper blade. In order to prevent the washing liquid from remaining on or dripping onto the windshield immediately after wiping, more than one wiping operation is performed without spraying the washing liquid.
Recently, the use of an imaging device such as a stereo camera that captures a front view from a vehicle and that is provided on the vehicle interior side of a windshield so as to control the vehicle for the sake of pre-crash safety, driving support, and the like has become widespread. In a vehicle having the imaging device, an imaging operation may be subject to detrimental effects and control of the vehicle will be affected.
In the technique disclosed in JP-A No. 2008-6971, it is possible to prevent a washer liquid from remaining on a windscreen after wiping by performing an additional wiping operation after spraying of the washer liquid has been stopped. However, even in such a case, it is unavoidable that the imaging operation will be temporarily negatively affected until the wiping operation finishes.